State Department spokesman Tom Casey told reporters in his office Monday that the United States had concerns about Bhutto's security before and after she returned to Pakistan.

And he disputed claims made Monday in the Washington Post and other newspapers by columnist Robert Novak that security issues had been ignored.

In his column, Novak wrote, "The assassination of Benazir Bhutto followed two months of urgent pleas to the State Department by her representatives for better protection. The U.S. reaction was that she was worried over nothing, expressing assurance that Pakistani President Pervez Musharraf would not let anything happen to her." Watch new video of Bhutto's assassination »

That is untrue, said the State Department's Casey.

"We discussed those concerns regularly both with her and officials from her party as well as with President Musharraf and with his government," he said.

"We always in every instance took those concerns seriously. We were very active in trying to ensure that any information we had that was relevant to her situation was passed on to her as well as those responsible for her security.

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"And it is simply untrue and I do not just simply understand why anyone, anywhere would assert that the United States either did not have concerns or minimized those concerns or was not very active in trying to ensure she was provided with whatever kind of security support she required."

Senior U.S. diplomats spoke several times with top members of Bhutto's Pakistan People's Party to discuss threats on her life, including at least two private face-to-face meetings, The Associated Press reported.

The diplomats also reviewed her security arrangement following a suicide bombing in October which marred her initial return to Pakistan from exile, U.S. officials told the AP.

"She knew people were trying to assassinate her," an intelligence official told AP. "We don't hold information back on possible attacks on foreign leaders and foreign countries."

However, the official added, that although the United States could share the information, "it's up to [the recipient] how they want to take action." E-mail to a friend

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